Battery electric vehicles make use of an electric drive motor for propulsion, and hybrid electric vehicles make use of an electric drive motor in conjunction with a conventional internal combustion engine for propulsion. Such vehicles include a battery pack including one or more cells electrically connected together. These cells store energy that may be used to supply electric power to the drive motor. The battery pack may also be referred to as a traction battery or a high voltage battery. The traction battery and associated components may generate substantial amounts of heat. This heat may interfere with proper functioning of the battery pack if not dissipated, and so a cooling system is desirable to maintain satisfactory battery operating temperatures. Such a cooling system must satisfy a variety of design considerations including cooling effectiveness and compact packaging, and minimally affect the performance of other vehicle systems.